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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

The effects of singing on blood pressure in classically trained singers

Broadwater, Kimberly Jaye. January 2002 (has links)
Thesis (D.M.A.)--Louisiana State University, 2002. / Includes bibliographical references.
142

Analysis of a dynamic pressure measuring system.

Blevins, Roger Allen, January 1970 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute, 1970. / Also available via the Internet.
143

A study of the relationship between peer influence and adolescent substance abuse : a social learning approach /

Poon, Wai-fong. January 2003 (has links)
Thesis (M. Soc. Sc.)--University of Hong Kong, 2003.
144

Blood Pressure Estimation Using Oscillometric Pulse Morphology

Mafi, Majid 25 January 2012 (has links)
This thesis work presents the analysis of Oscillometric blood pressure pulse waveform under different pressure points (Systolic, Mean Arterial, and Diastolic Pressures). Pulse waveforms' characteristics were determined from the waveforms at three different pressures and are compared for subjects at three different age groups. Estimation of blood pressure using a morphology based approach was done by using the change of pulse waveform characteristics at different pressure points. Pulse waveforms' characteristics that were obtained from pulse waveforms are utilized to estimate SBP, MAP, and DBP. The estimates obtained with pulse morphology based technique are compared with a BP measurement device and Maximum Amplitude Algorithm. Maximum slope of the pulse was also used for blood pressure estimation. The effect of movement and breathing on proposed method and MAA were compared and it was observed that breathing artifacts affect less the proposed method.
145

The influence of peer pressure on adolescent misbehaviour in schools

Memoir, Chimwamurombe January 2011 (has links)
<p>A favourable school atmosphere, in which adolescents behave positively, is one of the greatest concerns for teachers, administrators and parents. Although there are several different pressures leading to adolescent misbehaviour at school, the most contributing factors are peer pressure and the socio-economic status of the school. As adolescents enter the school, the peer group then functions as an important socializing agent for them. As peers socialize within their different school environments, individuals are forced to conform to the practices and opinions of the group. Usually this conformity is unconstructive and clashes with the parents&rsquo / and teachers&rsquo / expectations. The aim of this study was to examine the influence of peer pressure on adolescent misbehaviour in advantaged and disadvantaged&nbsp / schools. A quantitative methodological approach was used to conduct the study. The study was conducted with adolescents aged from&nbsp / 13 to 17 years in both advantaged and disadvantaged secondary (high) schools in Windhoek, Namibia. A sample of 300 participants was randomly stratified across the schools. The Exposure to Peer Pressure Control Scale (Allen &amp / Yen, 2002) and Child Behaviour Checklist&nbsp / questionnaires (Achenbach &amp / Edelbrock, 1987) were used to collect the data. Ethical considerations were carefully considered before and during the research procedure of data collection. The reliability of the instruments was checked by means of a pilot study. The data was analysed by means of the Statistical Package for Social Sciences (SPSS) version 18 to reveal descriptive and inferential statistics. Results showed a significant positive relationship between peer pressure and adolescent misbehaviour in schools. In addition, misbehaviour was also positively predicted in both advantaged and disadvantaged schools, with disadvantaged schools being significantly more influential. When comparing peer pressure and adolescent misbehaviours in both advantaged and disadvantaged schools, adolescents in&nbsp / is advantaged schools engaged significantly more in misbehaviour activities and also responded positively more to peer pressure than their counterparts in advantaged schools. Implications for further research were suggested.</p>
146

Blood Pressure Estimation Using Oscillometric Pulse Morphology

Mafi, Majid 25 January 2012 (has links)
This thesis work presents the analysis of Oscillometric blood pressure pulse waveform under different pressure points (Systolic, Mean Arterial, and Diastolic Pressures). Pulse waveforms' characteristics were determined from the waveforms at three different pressures and are compared for subjects at three different age groups. Estimation of blood pressure using a morphology based approach was done by using the change of pulse waveform characteristics at different pressure points. Pulse waveforms' characteristics that were obtained from pulse waveforms are utilized to estimate SBP, MAP, and DBP. The estimates obtained with pulse morphology based technique are compared with a BP measurement device and Maximum Amplitude Algorithm. Maximum slope of the pulse was also used for blood pressure estimation. The effect of movement and breathing on proposed method and MAA were compared and it was observed that breathing artifacts affect less the proposed method.
147

Structural and functional characterization of a lymphatic system using computational and experimental approaches

Madabushi Venugopal, Arun 15 May 2009 (has links)
The lymphatic system returns interstitial fluid back to the blood circulation. They have a network of vessels with numerous lymphangions, the segment of lymphatic vessel between two unidirectional valves. The valves aid in transporting lymph against a pressure gradient, in addition to the lymphangion pump which exhibit cyclical variations in diameter. Like blood vessels, baseline lymphatic tone is regulated with changes in transmural pressure; however, the transient response of lymphatic diastolic diameter following changes in transmural pressure has not been studied. The lymphangion pump is often described using cardiac analogies. However, since an active system empties into another active system in a lymphatic vessel, the analogy cannot characterize the principles governing optimal lymphatic vessel function. Furthermore, to optimize lymph flow there is also a need to characterize the lymphatic network structure. To characterize the transient diameter response of lymphatic segment, we used post-nodal bovine mesenteric lymphangions in an isobaric preparation and measured the diameter response to a step change in pressure. An immediate active reduction in enddiastolic diameter with each incremental increase in pressure was observed. To identify the principles governing optimal lymphatic vessel function, we applied the result obtained from optimizing the interaction of the heart-arterial system to measured lymphangion pressure-volume relationships. We assumed that the slope of end systolic pressure-volume relationship (Emax) is equal to the slope of end-diastolic relationship (Emin) above a cutoff pressure and Emax>Emin below the cutoff pressure. Unlike the heart, we found that stroke work is not optimized when Emax = Emin. However, there is a region where lymph flow is insensitive to changes in transmural pressure. To characterize the lymphatic network structure, we used an approximation of time-varying elastance model. We found there is an optimal length for the lymphangion when it produces maximal flow. To develop a fractal network model, we determined the ratio of radius and ratio of length of lymphangion at a confluence. Using conservation of mass and certain simplifying assumptions, we showed that the ratio of radius, as well as ratio of length of upstream lymphangion, to the downstream lymphangion at confluences is 1.26.
148

Determining Pressure Losses For Airflow In Residential Ductwork

Weaver, Kevin Douglas 2011 December 1900 (has links)
Airflow pressure losses through rigid metallic and non-metallic flexible ducts were studied and recommendations to improve the rating of flexible ducts were made as part of this study. The testing was done in compliance with ASHRAE Standard 120-1999, Methods of Testing to Determine Flow Resistance of HVAC Air Ducts and Fittings (ASHRAE 1999). Duct sizes of 6", 8", and 10" were tested in a positive pressure, blow-through configuration. An As-Built Test Protocol expands the test configurations specified by Standard 120-1999. Results of the current tests extend the existing ASHRAE/ACCA data for flexible duct which does not include pressure loss data for flexible ducts that are compressed beyond approximately 4%. The data from this study exhibit higher pressure drops than prior ACCA or ASHRAE data. Some configurations exhibit over ten times the pressure loss found in rigid duct or fully stretched flexible duct of the same diameter.
149

A study on the effect of misconception of ¡§pressure¡¨ and ¡§buoyancy¡¨ on the related problem solving ability for the middle school students.

Kuo, Shin-hung 12 January 2006 (has links)
Abstract The purpose of this study is to explore the effect of ¡§pressure¡¨ and ¡§buoyancy¡¨ misconceptions on the related problem solving ability for middle school students. The formal test was conducted upon 96 second-year middle school students in the Kaohsiung area. Both two-tier test and interview techniques were used to diagnose the students¡¦ misconceptions about pressure and buoyancy. The A-type and B-type situation questionnaires were the two tests used in this study. The test-retest reliabilities of these two tests are 0.84 and 0.82, respectively. Every student was required to complete the A-type questionnaire, and then take the B-type questionnaire a week later. After completing the tests, students were sample-selected as representatives for in-depth interviews. The interview for each student was based on his or her two-tier test. After dividing students into three levels within their own classes, two students were chosen from each level. The two tests¡¦ data were then analyzed and compared using statistical frequency distribution, descriptive analyses, t-test, and phi and Pearson product-moment correlation coefficients. The data from interview was transcribed into Word documents from the recorded interview tapes. The major results of this study are the following: 1. There was a significant correlation¡]P¡Õ.01¡^ between the two misconception tests. 2. There was a significant correlation¡]P¡Õ.05¡^between each misconception test and the students¡¦ school achievement. 3. There exist statistical significant differences on both A and B test scores between students from rural school from suburban school¡]P¡Õ.01¡^. This study also categorized the ¡§pressure¡¨ and ¡§buoyancy¡¨ misconceptions and unique misconceptions from different situations as tested by the A-type and B-type questionnaires.
150

Experimental Study of Gravity Standing Waves Field

Ho, Chun-Yeh 11 February 2003 (has links)
ABSTRACT This paper treats the standing waves formed by two progressive waves possessing same properties but opposite direction in stationary atmosphere and uniform depth. The third-order approximation to two-wave trains interactions obtained by Chen¡]1990¡^is cited. From the solution that can be reduced to the cases such as standing waves, the properties resulted in standing wave due to the nonlinear interactions between two wave trains intersection, particularly, the two peaks of wave pressure, are described clearly. Furthermore, the profile, pressure and angular frequency is also verified in good agreement with the experimental results.

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